外源锌浸种对大豆种子萌发、大豆芽生长及锌积累的影响

Influences of Exogenous Zinc Soaking on Seed Germination,Sprout Growth of Soybean and Zinc Accumulation in the Sprouts

采用不同浓度的锌溶液(0～100μg·mL-1)浸种8 h后水培5 d培育大豆芽,测定了外源锌浸种后大豆种子吸水率、发芽率和大豆芽生长过程中芽长、鲜重、含水量、生物产率及锌积累,并对富锌大豆芽中锌的生物可利用性进行了评估。结果表明:10～100μg·mL-1外源锌浸种可以提高大豆种子的吸水率,对大豆芽芽长、鲜重、含水量和生物产率的影响不明显。当浸种液中锌浓度超过30μg·mL-1时,大豆种子的萌发受到显著抑制(P<0.05)。随着浸种液中锌浓度的升高,大豆芽可食部分、不可食部分的含锌量均较对照显著增加(P<0.05),且不可食部分大于可食部分。从锌元素生物利用性上看,大豆芽可食部分在外源锌浓度10μg·mL-1时、不可食部分在外源锌浓度10～30μg·mL-1范围内锌的生物可接受率均显著高于对照(P<0.05),且不可食部分大于可食部分。综上可见,在不影响种子萌发和芽苗生长的前提下,10μg·mL-1的外源锌浸种有利于大豆芽对锌的积累。

The objective of current research was to ascertain the influences of exogenous zinc（Zn2＋）soaking on cultivating zinc-enriched soybean sprouts.Soybean seeds were soaked for 8 h in zinc sulfate solutions containing different concentration of zinc（0,10,20,30,40,50,60,80,100μg·mL-1）and then cultivated for 5 days with deionized water for the preparation of sprouts.The water absorption rate and germination rate of seeds,and the length,fresh weight,water content,biological yield and zinc accumulation of soybean sprouts were determined.Meanwhile,the bioaccessibility of zinc from soybean sprouts was also evaluated using an in vitro digestion/dialysis method.The obtained results showed that exogenous zinc soaking with 10-100μg·mL-1 Zn solutions could improve the water absorption rate of soybean seeds,but there was no obvious effect on the growth of soybean sprouts.Soybean seed germination was inhibited obviously（P0.05）when CZn2＋ in soaking solution was great than or equal to 30μg·mL-1.Zinc contents in edible or inedible part of sprouts increased significantly（P0.05）with zinc concentration of soaking solutions.The content and bioaccessibility of zinc from inedible part of sprouts were higher than those from edible part.The bioaccessibility of zinc from edible and inedible part exceeded greatly over those of CK（P0.05）with the concentration of soaking solutions for edible and inedible part respectively at 10μg·mL-1 and 10-30μg·mL-1.In conclusion,exogenous zinc soaking with zinc sulfate solution of appropriate concentration（10μg·mL-1）can facilitate the zinc accumulation in soybean sprouts in circumstances where normal seed germination and sprout growth are guaranteed.